Mastering TypeScript Integration Testing with Cypress: A Practical Guide

Is your web application delivering a top-notch user experience? It's time to find out. Welcome to the world of integration testing with TypeScript and Cypress—a journey that empowers you to ensure your application runs smoothly from start to finish. In this article, we'll dive into a practical example: testing a TypeScript-powered Todo List app. You'll learn how to set up Cypress, write effective integration tests, and gain the confidence that your app works flawlessly. Let's get started.

By the way, if you also want to read about Unit testing and improving code quality in just 6 steps, read here.

Section 1: Setting Up the Todo List Application

Step 1: Create a New React App

Open your terminal and run the following commands to create a new React app with TypeScript:

npx create-react-app todo-list --template typescript
cd todo-list

Step 2: Start the Development Server

Start the development server:

npm start

Your Todo List application will be available at http://localhost:3000.

Section 2: Implementing the Todo List App

Step 3: Build the Todo List App

Replace the content of src/App.tsx with the following code to create the Todo List application:

This code sets up a basic Todo List app that uses the LocalStorageManager to store tasks in local storage.

Section 3: Setting Up Cypress for Integration Testing

Step 4: Install Cypress

Open your terminal and run the following commands to install Cypress as a development dependency:

npm install cypress --save-dev

Step 5: Open Cypress

Launch Cypress by running the following command:

npx cypress open

Cypress Test Runner will open, allowing you to create and run integration tests.

Section 4: Writing Integration Tests with Cypress

Step 6: Organize Folder Structure

Create a modular folder structure for your Cypress tests:

cypress/
  fixtures/
  e2e/
    todo/
      actions.ts
      selectors.ts
      tests.cy.ts
  plugins/
  support/

Step 7: Define Actions